How do I add 1 int to another script

Hi all, so I have a script as below, which gets no errors but does not do what I want it to do, I am trying to add 1 int to the score var in the Shoot script from this script, but it adds multiples to the score var in the Shoot script, would anyone know how I can fix this. Thank you.

 using UnityEngine;
 using System.Collections;
 
 public class TargetHealthA : MonoBehaviour 
 {
     public float health = 35f;
     public Animation targetDown;
     public float lessOne = 0.1f;
     public int addOne = 1;
     public Shoot addScore;
 
     
     void Start()
     {
         targetDown = GetComponent<Animation> ();
         addScore = GetComponent<Shoot> ();
     }
     
     public void RemoveHealth(float enemyDamage)
     {
         health -= enemyDamage;
     }
     
     void Update()
     {
         if (health <= 0) 
         {
             Dead ();
         }
     }
 
     void Dead()
     {
         Shoot.score += 1;
         targetDown.Play ("TargetDownA");
         Destroy (gameObject, 0.5f);
     }
 }

I have already tried to use using

using UnityEngine; 
using System.Collections; 

public class TargetHealthA : MonoBehaviour 
{ 
   public float health = 35f;
   public Animation targetDown;
   public float lessOne = 0.1f;
   public Shoot addScore; 

   void Start() 
   { 
      targetDown = GetComponent<Animation> ();
      addScore = GetComponent<Shoot> ();
   } 

   public void RemoveHealth(float enemyDamage) 
   { 
      health -= enemyDamage; 
   } 

   void Update() 
   { 
     if (health <= 0)
     {
       Dead ();
     }
   }

   void Dead() 
   { 
      GetComponent<Shoot>(), AddScore();
      targetDown.Play ("TargetDownA"); 
      Destroy (gameObject, 0.5f);
   } 
}

For the line GetComponent(),AddScore(); I do not know what is meant to go infront of this, I have searched through Answers but most responses are about how to set it up as in void Start varName = GetComponent();, but dont explain how to access the script through another function.

The Shoot Script is about 600 lines long so I cant post it here, but everything works perfectly in it bar adding the 1 int when the Target is hit, but here is the section for the score

   void Update() 
   { 
      scoreText.text ="Score : "+ score.ToString 
   }

   public void AddScore(int addScore) 
   { 
      score += addOne; 
   }'

As I say when I use Shoot.score += 1 from the first script shown I get multiples adding to the score not just 1 int as I am looking for. Could someone please explain to me how to fix these issues. Thank you. Joxer

I explain it very clearly here:

and here